Ver­si­on 1.2, Novem­ber 2002

Copy­right © 2000,2001,2002 Free Soft­ware Foun­da­ti­on, Inc.
51 Fran­k­lin St, Fifth Floor, Bos­ton, MA 02110–1301 USA
Ever­yo­ne is per­mit­ted to copy and dis­tri­bu­te ver­ba­tim copies
of this licen­se docu­ment, but chan­ging it is not allo­wed.


The pur­po­se of this Licen­se is to make a manu­al, text­book, or other func­tio­nal and use­ful docu­ment “free” in the sen­se of free­dom: to assu­re ever­yo­ne the effec­tive free­dom to copy and redis­tri­bu­te it, with or without modi­fy­ing it, eit­her com­mer­ci­al­ly or non­com­mer­ci­al­ly. Secon­da­ri­ly, this Licen­se pre­ser­ves for the aut­hor and publisher a way to get credit for their work, while not being con­s­i­de­red respon­si­ble for modi­fi­ca­ti­ons made by others.

This Licen­se is a kind of “copy­left”, which means that deri­va­ti­ve works of the docu­ment must them­sel­ves be free in the same sen­se. It com­ple­ments the GNU Gene­ral Public Licen­se, which is a copy­left licen­se desi­gned for free soft­ware.

We have desi­gned this Licen­se in order to use it for manu­als for free soft­ware, becau­se free soft­ware needs free docu­men­ta­ti­on: a free pro­gram should come with manu­als pro­vi­ding the same free­doms that the soft­ware does. But this Licen­se is not limi­ted to soft­ware manu­als; it can be used for any tex­tu­al work, regard­less of sub­ject mat­ter or whe­ther it is published as a prin­ted book. We recom­mend this Licen­se princi­pal­ly for works who­se pur­po­se is inst­ruc­tion or refe­rence.


This Licen­se app­lies to any manu­al or other work, in any medi­um, that con­ta­ins a noti­ce pla­ced by the copy­right hol­der say­ing it can be dis­tri­bu­t­ed under the terms of this Licen­se. Such a noti­ce grants a world-wide, royal­ty-free licen­se, unli­mi­ted in dura­ti­on, to use that work under the con­di­ti­ons sta­ted her­ein. The “Docu­ment”, below, refers to any such manu­al or work. Any mem­ber of the public is a licen­see, and is addres­sed as “you”. You accept the licen­se if you copy, modi­fy or dis­tri­bu­te the work in a way requi­ring per­mis­si­on under copy­right law.

A “Modi­fied Ver­si­on” of the Docu­ment means any work con­tai­ning the Docu­ment or a por­ti­on of it, eit­her copied ver­ba­tim, or with modi­fi­ca­ti­ons and/or trans­la­ted into ano­t­her lan­guage.

A “Secon­da­ry Sec­tion” is a named appen­dix or a front-mat­ter sec­tion of the Docu­ment that deals exclu­si­ve­ly with the rela­ti­ons­hip of the publishers or aut­hors of the Docu­ment to the Document’s over­all sub­ject (or to rela­ted mat­ters) and con­ta­ins not­hing that could fall direct­ly wit­hin that over­all sub­ject. (Thus, if the Docu­ment is in part a text­book of mathe­ma­tics, a Secon­da­ry Sec­tion may not exp­lain any mathe­ma­tics.) The rela­ti­ons­hip could be a mat­ter of his­to­ri­cal con­nec­tion with the sub­ject or with rela­ted mat­ters, or of legal, com­mer­ci­al, phi­lo­so­phi­cal, ethi­cal or poli­ti­cal posi­ti­on regar­ding them.

The “Inva­ri­ant Sec­tions” are cer­tain Secon­da­ry Sec­tions who­se tit­les are desi­gna­ted, as being tho­se of Inva­ri­ant Sec­tions, in the noti­ce that says that the Docu­ment is released under this Licen­se. If a sec­tion does not fit the above defi­ni­ti­on of Secon­da­ry then it is not allo­wed to be desi­gna­ted as Inva­ri­ant. The Docu­ment may con­tain zero Inva­ri­ant Sec­tions. If the Docu­ment does not iden­ti­fy any Inva­ri­ant Sec­tions then the­re are none.

The “Cover Texts” are cer­tain short pas­sa­ges of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the noti­ce that says that the Docu­ment is released under this Licen­se. A Front-Cover Text may be at most 5 wor­ds, and a Back-Cover Text may be at most 25 wor­ds.

A “Trans­pa­rent” copy of the Docu­ment means a machi­ne-read­a­ble copy, rep­re­sen­ted in a for­mat who­se spe­ci­fi­ca­ti­on is avail­ab­le to the gene­ral public, that is sui­ta­ble for revi­sing the docu­ment strai­ght­for­ward­ly with gene­ric text edi­tors or (for images com­po­sed of pixels) gene­ric paint pro­grams or (for drawings) some wide­ly avail­ab­le drawing edi­tor, and that is sui­ta­ble for input to text for­mat­ters or for auto­ma­tic trans­la­ti­on to a varie­ty of for­mats sui­ta­ble for input to text for­mat­ters. A copy made in an other­wi­se Trans­pa­rent file for­mat who­se mark­up, or absence of mark­up, has been arran­ged to thwart or dis­cou­ra­ge sub­se­quent modi­fi­ca­ti­on by readers is not Trans­pa­rent. An image for­mat is not Trans­pa­rent if used for any sub­stan­ti­al amount of text. A copy that is not “Trans­pa­rent” is cal­led “Opa­que”.

Examp­les of sui­ta­ble for­mats for Trans­pa­rent copies inclu­de plain ASCII without mark­up, Tex­in­fo input for­mat, LaTeX input for­mat, SGML or XML using a publicly avail­ab­le DTD, and stan­dard-con­for­ming simp­le HTML, Post­Script or PDF desi­gned for human modi­fi­ca­ti­on. Examp­les of trans­pa­rent image for­mats inclu­de PNG, XCF and JPG. Opa­que for­mats inclu­de pro­prie­ta­ry for­mats that can be read and edi­ted only by pro­prie­ta­ry word pro­ces­sors, SGML or XML for which the DTD and/or pro­ces­sing tools are not gene­ral­ly avail­ab­le, and the machi­ne-gene­ra­ted HTML, Post­Script or PDF pro­du­ced by some word pro­ces­sors for out­put pur­po­ses only.

The “Tit­le Page” means, for a prin­ted book, the tit­le page its­elf, plus such fol­lo­wing pages as are nee­ded to hold, legi­b­ly, the mate­ri­al this Licen­se requi­res to appe­ar in the tit­le page. For works in for­mats which do not have any tit­le page as such, “Tit­le Page” means the text near the most pro­mi­nent appearan­ce of the work’s tit­le, pre­ce­ding the begin­ning of the body of the text.

A sec­tion “Ent­it­led XYZ” means a named sub­u­nit of the Docu­ment who­se tit­le eit­her is pre­cise­ly XYZ or con­ta­ins XYZ in par­en­the­ses fol­lo­wing text that trans­la­tes XYZ in ano­t­her lan­guage. (Here XYZ stands for a spe­ci­fic sec­tion name men­tio­ned below, such as “Ack­now­led­ge­ments”, “Dedi­ca­ti­ons”, “Endor­se­ments”, or “Histo­ry”.) To “Pre­ser­ve the Tit­le” of such a sec­tion when you modi­fy the Docu­ment means that it remains a sec­tion “Ent­it­led XYZ” accord­ing to this defi­ni­ti­on.

The Docu­ment may inclu­de War­ran­ty Dis­c­lai­mers next to the noti­ce which sta­tes that this Licen­se app­lies to the Docu­ment. The­se War­ran­ty Dis­c­lai­mers are con­s­i­de­red to be inclu­ded by refe­rence in this Licen­se, but only as regards dis­c­lai­ming war­ran­ties: any other impli­ca­ti­on that the­se War­ran­ty Dis­c­lai­mers may have is void and has no effect on the mea­ning of this Licen­se.


You may copy and dis­tri­bu­te the Docu­ment in any medi­um, eit­her com­mer­ci­al­ly or non­com­mer­ci­al­ly, pro­vi­ded that this Licen­se, the copy­right noti­ces, and the licen­se noti­ce say­ing this Licen­se app­lies to the Docu­ment are repro­du­ced in all copies, and that you add no other con­di­ti­ons whatsoever to tho­se of this Licen­se. You may not use tech­ni­cal mea­su­res to obst­ruct or con­trol the rea­ding or fur­t­her copy­ing of the copies you make or dis­tri­bu­te. Howe­ver, you may accept com­pen­sa­ti­on in exchan­ge for copies. If you dis­tri­bu­te a lar­ge enough num­ber of copies you must also fol­low the con­di­ti­ons in sec­tion 3.

You may also lend copies, under the same con­di­ti­ons sta­ted above, and you may publicly dis­play copies.


If you publish prin­ted copies (or copies in media that com­mon­ly have prin­ted covers) of the Docu­ment, num­be­ring more than 100, and the Document’s licen­se noti­ce requi­res Cover Texts, you must enc­lo­se the copies in covers that car­ry, clear­ly and legi­b­ly, all the­se Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clear­ly and legi­b­ly iden­ti­fy you as the publisher of the­se copies. The front cover must pre­sent the full tit­le with all wor­ds of the tit­le equal­ly pro­mi­nent and visi­ble. You may add other mate­ri­al on the covers in addi­ti­on. Copy­ing with chan­ges limi­ted to the covers, as long as they pre­ser­ve the tit­le of the Docu­ment and satis­fy the­se con­di­ti­ons, can be trea­ted as ver­ba­tim copy­ing in other respects.

If the requi­red texts for eit­her cover are too volu­mi­nous to fit legi­b­ly, you should put the first ones listed (as many as fit rea­son­ab­ly) on the actu­al cover, and con­ti­nue the rest onto adja­cent pages.

If you publish or dis­tri­bu­te Opa­que copies of the Docu­ment num­be­ring more than 100, you must eit­her inclu­de a machi­ne-read­a­ble Trans­pa­rent copy along with each Opa­que copy, or sta­te in or with each Opa­que copy a com­pu­ter-net­work loca­ti­on from which the gene­ral net­work-using public has access to down­load using public-stan­dard net­work pro­to­cols a com­ple­te Trans­pa­rent copy of the Docu­ment, free of added mate­ri­al. If you use the lat­ter opti­on, you must take rea­son­ab­ly pru­dent steps, when you begin dis­tri­bu­ti­on of Opa­que copies in quan­ti­ty, to ensu­re that this Trans­pa­rent copy will remain thus acces­si­ble at the sta­ted loca­ti­on until at least one year after the last time you dis­tri­bu­te an Opa­que copy (direct­ly or through your agents or retailers) of that edi­ti­on to the public.

It is requested, but not requi­red, that you con­tact the aut­hors of the Docu­ment well befo­re redis­tri­bu­ting any lar­ge num­ber of copies, to give them a chan­ce to pro­vi­de you with an updated ver­si­on of the Docu­ment.


You may copy and dis­tri­bu­te a Modi­fied Ver­si­on of the Docu­ment under the con­di­ti­ons of sec­tions 2 and 3 above, pro­vi­ded that you release the Modi­fied Ver­si­on under pre­cise­ly this Licen­se, with the Modi­fied Ver­si­on fil­ling the role of the Docu­ment, thus licen­sing dis­tri­bu­ti­on and modi­fi­ca­ti­on of the Modi­fied Ver­si­on to whoever pos­ses­ses a copy of it. In addi­ti­on, you must do the­se things in the Modi­fied Ver­si­on:

Mit­ten­text Plea­se gene­ra­te and pas­te your ad code here. If left empty, the ad loca­ti­on will be high­light­ed on your blog pages with a remin­der to enter your code.

* A. Use in the Tit­le Page (and on the covers, if any) a tit­le dis­tinct from that of the Docu­ment, and from tho­se of pre­vious ver­si­ons (which should, if the­re were any, be listed in the Histo­ry sec­tion of the Docu­ment). You may use the same tit­le as a pre­vious ver­si­on if the ori­gi­nal publisher of that ver­si­on gives per­mis­si­on.
* B. List on the Tit­le Page, as aut­hors, one or more per­sons or ent­i­ties respon­si­ble for aut­hor­ship of the modi­fi­ca­ti­ons in the Modi­fied Ver­si­on, toge­ther with at least five of the princi­pal aut­hors of the Docu­ment (all of its princi­pal aut­hors, if it has fewer than five), unless they release you from this requi­re­ment.
* C. Sta­te on the Tit­le page the name of the publisher of the Modi­fied Ver­si­on, as the publisher.
* D. Pre­ser­ve all the copy­right noti­ces of the Docu­ment.
* E. Add an appro­pria­te copy­right noti­ce for your modi­fi­ca­ti­ons adja­cent to the other copy­right noti­ces.
* F. Inclu­de, imme­dia­te­ly after the copy­right noti­ces, a licen­se noti­ce giving the public per­mis­si­on to use the Modi­fied Ver­si­on under the terms of this Licen­se, in the form shown in the Adden­dum below.
* G. Pre­ser­ve in that licen­se noti­ce the full lists of Inva­ri­ant Sec­tions and requi­red Cover Texts given in the Document’s licen­se noti­ce.
* H. Inclu­de an unal­te­red copy of this Licen­se.
* I. Pre­ser­ve the sec­tion Ent­it­led “Histo­ry”, Pre­ser­ve its Tit­le, and add to it an item sta­ting at least the tit­le, year, new aut­hors, and publisher of the Modi­fied Ver­si­on as given on the Tit­le Page. If the­re is no sec­tion Ent­it­led “Histo­ry” in the Docu­ment, crea­te one sta­ting the tit­le, year, aut­hors, and publisher of the Docu­ment as given on its Tit­le Page, then add an item describing the Modi­fied Ver­si­on as sta­ted in the pre­vious sen­tence.
* J. Pre­ser­ve the net­work loca­ti­on, if any, given in the Docu­ment for public access to a Trans­pa­rent copy of the Docu­ment, and like­wi­se the net­work loca­ti­ons given in the Docu­ment for pre­vious ver­si­ons it was based on. The­se may be pla­ced in the “Histo­ry” sec­tion. You may omit a net­work loca­ti­on for a work that was published at least four years befo­re the Docu­ment its­elf, or if the ori­gi­nal publisher of the ver­si­on it refers to gives per­mis­si­on.
* K. For any sec­tion Ent­it­led “Ack­now­led­ge­ments” or “Dedi­ca­ti­ons”, Pre­ser­ve the Tit­le of the sec­tion, and pre­ser­ve in the sec­tion all the sub­s­tan­ce and tone of each of the con­tri­bu­tor ack­now­led­ge­ments and/or dedi­ca­ti­ons given ther­ein.
* L. Pre­ser­ve all the Inva­ri­ant Sec­tions of the Docu­ment, unal­te­red in their text and in their tit­les. Sec­tion num­bers or the equi­va­lent are not con­s­i­de­red part of the sec­tion tit­les.
* M. Dele­te any sec­tion Ent­it­led “Endor­se­ments”. Such a sec­tion may not be inclu­ded in the Modi­fied Ver­si­on.
* N. Do not retit­le any exis­ting sec­tion to be Ent­it­led “Endor­se­ments” or to con­flict in tit­le with any Inva­ri­ant Sec­tion.
* O. Pre­ser­ve any War­ran­ty Dis­c­lai­mers.

If the Modi­fied Ver­si­on inclu­des new front-mat­ter sec­tions or appen­di­ces that qua­li­fy as Secon­da­ry Sec­tions and con­tain no mate­ri­al copied from the Docu­ment, you may at your opti­on desi­gna­te some or all of the­se sec­tions as inva­ri­ant. To do this, add their tit­les to the list of Inva­ri­ant Sec­tions in the Modi­fied Version’s licen­se noti­ce. The­se tit­les must be dis­tinct from any other sec­tion tit­les.

You may add a sec­tion Ent­it­led “Endor­se­ments”, pro­vi­ded it con­ta­ins not­hing but endor­se­ments of your Modi­fied Ver­si­on by various parties–for examp­le, state­ments of peer review or that the text has been appro­ved by an orga­ni­za­ti­on as the aut­ho­ri­ta­ti­ve defi­ni­ti­on of a stan­dard.

You may add a pas­sa­ge of up to five wor­ds as a Front-Cover Text, and a pas­sa­ge of up to 25 wor­ds as a Back-Cover Text, to the end of the list of Cover Texts in the Modi­fied Ver­si­on. Only one pas­sa­ge of Front-Cover Text and one of Back-Cover Text may be added by (or through arran­ge­ments made by) any one ent­i­ty. If the Docu­ment alre­ady inclu­des a cover text for the same cover, pre­vious­ly added by you or by arran­ge­ment made by the same ent­i­ty you are acting on behalf of, you may not add ano­t­her; but you may replace the old one, on expli­cit per­mis­si­on from the pre­vious publisher that added the old one.

The author(s) and publisher(s) of the Docu­ment do not by this Licen­se give per­mis­si­on to use their names for publi­ci­ty for or to assert or imply endor­se­ment of any Modi­fied Ver­si­on.


You may com­bi­ne the Docu­ment with other docu­ments released under this Licen­se, under the terms defi­ned in sec­tion 4 above for modi­fied ver­si­ons, pro­vi­ded that you inclu­de in the com­bi­na­ti­on all of the Inva­ri­ant Sec­tions of all of the ori­gi­nal docu­ments, unmo­di­fied, and list them all as Inva­ri­ant Sec­tions of your com­bi­ned work in its licen­se noti­ce, and that you pre­ser­ve all their War­ran­ty Dis­c­lai­mers.

The com­bi­ned work need only con­tain one copy of this Licen­se, and mul­ti­ple iden­ti­cal Inva­ri­ant Sec­tions may be repla­ced with a sin­gle copy. If the­re are mul­ti­ple Inva­ri­ant Sec­tions with the same name but dif­fe­rent con­tents, make the tit­le of each such sec­tion uni­que by adding at the end of it, in par­en­the­ses, the name of the ori­gi­nal aut­hor or publisher of that sec­tion if known, or else a uni­que num­ber. Make the same adjust­ment to the sec­tion tit­les in the list of Inva­ri­ant Sec­tions in the licen­se noti­ce of the com­bi­ned work.

In the com­bi­na­ti­on, you must com­bi­ne any sec­tions Ent­it­led “Histo­ry” in the various ori­gi­nal docu­ments, for­ming one sec­tion Ent­it­led “Histo­ry”; like­wi­se com­bi­ne any sec­tions Ent­it­led “Ack­now­led­ge­ments”, and any sec­tions Ent­it­led “Dedi­ca­ti­ons”. You must dele­te all sec­tions Ent­it­led “Endor­se­ments”.


You may make a collec­tion con­sis­ting of the Docu­ment and other docu­ments released under this Licen­se, and replace the indi­vi­du­al copies of this Licen­se in the various docu­ments with a sin­gle copy that is inclu­ded in the collec­tion, pro­vi­ded that you fol­low the rules of this Licen­se for ver­ba­tim copy­ing of each of the docu­ments in all other respects.

You may extract a sin­gle docu­ment from such a collec­tion, and dis­tri­bu­te it indi­vi­dual­ly under this Licen­se, pro­vi­ded you insert a copy of this Licen­se into the extrac­ted docu­ment, and fol­low this Licen­se in all other respects regar­ding ver­ba­tim copy­ing of that docu­ment.


A com­pi­la­ti­on of the Docu­ment or its deri­va­ti­ves with other sepa­ra­te and inde­pen­dent docu­ments or works, in or on a volu­me of a sto­ra­ge or dis­tri­bu­ti­on medi­um, is cal­led an “aggre­ga­te” if the copy­right resul­ting from the com­pi­la­ti­on is not used to limit the legal rights of the compilation’s users bey­ond what the indi­vi­du­al works per­mit. When the Docu­ment is inclu­ded in an aggre­ga­te, this Licen­se does not app­ly to the other works in the aggre­ga­te which are not them­sel­ves deri­va­ti­ve works of the Docu­ment.

If the Cover Text requi­re­ment of sec­tion 3 is app­li­ca­ble to the­se copies of the Docu­ment, then if the Docu­ment is less than one half of the ent­i­re aggre­ga­te, the Document’s Cover Texts may be pla­ced on covers that bra­cket the Docu­ment wit­hin the aggre­ga­te, or the elec­tro­nic equi­va­lent of covers if the Docu­ment is in elec­tro­nic form. Other­wi­se they must appe­ar on prin­ted covers that bra­cket the who­le aggre­ga­te.


Trans­la­ti­on is con­s­i­de­red a kind of modi­fi­ca­ti­on, so you may dis­tri­bu­te trans­la­ti­ons of the Docu­ment under the terms of sec­tion 4. Repla­cing Inva­ri­ant Sec­tions with trans­la­ti­ons requi­res spe­cial per­mis­si­on from their copy­right hol­ders, but you may inclu­de trans­la­ti­ons of some or all Inva­ri­ant Sec­tions in addi­ti­on to the ori­gi­nal ver­si­ons of the­se Inva­ri­ant Sec­tions. You may inclu­de a trans­la­ti­on of this Licen­se, and all the licen­se noti­ces in the Docu­ment, and any War­ran­ty Dis­c­lai­mers, pro­vi­ded that you also inclu­de the ori­gi­nal English ver­si­on of this Licen­se and the ori­gi­nal ver­si­ons of tho­se noti­ces and dis­c­lai­mers. In case of a dis­agree­ment bet­ween the trans­la­ti­on and the ori­gi­nal ver­si­on of this Licen­se or a noti­ce or dis­c­lai­mer, the ori­gi­nal ver­si­on will pre­vail.

If a sec­tion in the Docu­ment is Ent­it­led “Ack­now­led­ge­ments”, “Dedi­ca­ti­ons”, or “Histo­ry”, the requi­re­ment (sec­tion 4) to Pre­ser­ve its Tit­le (sec­tion 1) will typi­cal­ly requi­re chan­ging the actu­al tit­le.


You may not copy, modi­fy, sub­li­cen­se, or dis­tri­bu­te the Docu­ment except as express­ly pro­vi­ded for under this Licen­se. Any other attempt to copy, modi­fy, sub­li­cen­se or dis­tri­bu­te the Docu­ment is void, and will auto­ma­ti­cal­ly ter­mi­na­te your rights under this Licen­se. Howe­ver, par­ties who have recei­ved copies, or rights, from you under this Licen­se will not have their licen­ses ter­mi­na­ted so long as such par­ties remain in full com­pli­an­ce.


The Free Soft­ware Foun­da­ti­on may publish new, revi­sed ver­si­ons of the GNU Free Docu­men­ta­ti­on Licen­se from time to time. Such new ver­si­ons will be simi­lar in spi­rit to the pre­sent ver­si­on, but may dif­fer in detail to address new pro­blems or con­cerns. See

Each ver­si­on of the Licen­se is given a dis­tin­guis­hing ver­si­on num­ber. If the Docu­ment spe­ci­fies that a par­ti­cu­lar num­be­red ver­si­on of this Licen­se “or any later ver­si­on” app­lies to it, you have the opti­on of fol­lo­wing the terms and con­di­ti­ons eit­her of that spe­ci­fied ver­si­on or of any later ver­si­on that has been published (not as a draft) by the Free Soft­ware Foun­da­ti­on. If the Docu­ment does not spe­ci­fy a ver­si­on num­ber of this Licen­se, you may choo­se any ver­si­on ever published (not as a draft) by the Free Soft­ware Foun­da­ti­on.

ADDENDUM: How to use this License for your documents

To use this Licen­se in a docu­ment you have writ­ten, inclu­de a copy of the Licen­se in the docu­ment and put the fol­lo­wing copy­right and licen­se noti­ces just after the tit­le page:

Copy­right © YEAR YOUR NAME.
Per­mis­si­on is gran­ted to copy, dis­tri­bu­te and/or modi­fy this docu­ment
under the terms of the GNU Free Docu­men­ta­ti­on Licen­se, Ver­si­on 1.2
or any later ver­si­on published by the Free Soft­ware Foun­da­ti­on;
with no Inva­ri­ant Sec­tions, no Front-Cover Texts, and no Back-Cover Texts.
A copy of the licen­se is inclu­ded in the sec­tion ent­it­led
“GNU Free Docu­men­ta­ti­on Licen­se”.

If you have Inva­ri­ant Sec­tions, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

with the Inva­ri­ant Sec­tions being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Inva­ri­ant Sec­tions without Cover Texts, or some other com­bi­na­ti­on of the three, mer­ge tho­se two alter­na­ti­ves to suit the situa­ti­on.

If your docu­ment con­ta­ins nont­ri­vi­al examp­les of pro­gram code, we recom­mend releasing the­se examp­les in par­al­lel under your choice of free soft­ware licen­se, such as the GNU Gene­ral Public Licen­se, to per­mit their use in free soft­ware.